Selection and application of antifungal VOCs-producing yeasts as biocontrol agents of grey mould in fruits.

Rotting caused by grey mould (Botrytis cinerea) is a concerning disease for numerous crops both pre- and postharvest stages. Application of antagonistic yeasts is a promising strategy for controlling grey mould incidence which could mitigate undesirable consequences of using synthetic fungicides. In this work, a screening for detection of yeasts isolated from figs producers of antifungal volatile organic compounds (VOCs) were performed by confrontation in double dishes systems. Eleven out of 34 yeasts confronted reduced B. cinerea growth parameter in vitro. This reduction was correlated (p ≤ 0.050) with the production of 10 volatile compounds: two acids (acetic acid and octanoic acid), 7 esters (Ethyl propionate, n-Propyl acetate, Isobutyl acetate, 2-methylbutyl acetate, furfuryl acetate, phenylmethyl acetate, 2-phenylethyl acetate) and one ketone (Heptan-2-one). In bases on in vitro assay, Hanseniaspora uvarum 793 was applied to in vivo assays with strawberries and cherries. The reduction of incidence of B. cinerea in strawberries at 7 °C and 25 °C was 54.9 and 72.1% after 6 and 3 days, respectively. The reduction of incidence of B. cinerea in cherries at 7 °C and 25 °C was 48.9 and 45.6% after 5 and 4 days, respectively. These results showed that VOCs produced by Hanseniaspora uvarum 793 are effective in the control of incidence of Botrytis cinerea in fruits, being a potential alternative to chemical fungicide.

Gene expression of Aspergillus flavus strains on a cheese model system to control aflatoxin production.

The expression of genes associated with aflatoxin biosynthesis by different Aspergillus flavus strains growing on a cheese model system has not been studied. To control aflatoxin biosynthesis, it would be useful to understand the changes in gene expression during cheesemaking and relate those changes to toxin production. The objective of this study was to evaluate the effects of pH, water activity, and temperature on the expression of 2 regulatory genes (aflR and aflS) and 1 structural gene (aflP) involved in aflatoxin biosynthesis, using 3 aflatoxigenic A. flavus strains growing on a cheese-based medium and reverse-transcription real-time PCR. The gene expression patterns were influenced by A. flavus strain and environmental conditions. The structural gene aflP and the regulatory genes aflR and aflS showed similar expression patterns in each A. flavus strain, but we also observed inter-strain differences. We observed the highest expression levels at 6 and 9 d of incubation by A. flavus strains CQ8 and CQ103, and saw a decrease in the days following. Strain CQ7 showed the lowest expression of these genes. We observed the highest expression levels of these genes at pH 5.5, water activity 0.95, and 20 to 25°C; strain CQ103 showed a different pattern for the aflS gene, with maximum expression at pH 6.0 on d 6 of incubation. For the 3 strains, we found a strong correlation between the relative expression of the aflR and aflS genes and the concentration of aflatoxins under conditions that simulated cheese ripening. Control strategies to avoid aflatoxin contamination during cheesemaking could use the detection of regulatory gene expression.

Effect of plant density and harvesting type on yield and quality of fresh and dried peppers and paprika.

BACKGROUND: Traditionally, peppers (Capsicum annuum L.) of Jaranda variety used for the production of smoked paprika are harvested manually in the north of Extremadura (Spain). Mechanical harvesting is necessary to improve the profitability of this crop. The present study aimed to evaluate the effect of plant density (D1 = 36 765 and D2 = 73 530 plants ha-1 ) and harvesting type (manual or mechanical) on the yield and quality of fresh, dried and powdered peppers. RESULTS: The increase in plant density increased marketable yield per hectare, although the yield per plant decreased. With mechanical harvesting, the optimal density was D2 (15 151 kg ha-1 ) over D1 (12 493 kg ha-1 ). After processing the fruits, the application of D2 and mechanical harvesting significantly improved quality parameters, such as a*, ASTA (American Spice Trade Association) units and carotenoide concentration, primarily capsanthin. CONCLUSION: The cultural practices tested provided an adequate productivity of fresh pepper and a better quality of the final product. According to the results of the present study, the increase in plant density and the substitution of manual harvesting by mechanical harvesting could be profitable practices with respect to the Jaranda variety of pepper used for the manufacture of smoked paprika. These practices maintain the main quality parameters of dried peppers and paprika. © 2018 Society of Chemical Industry.

The growth and aflatoxin production of Aspergillus flavus strains on a cheese model system are influenced by physicochemical factors.

Traditional cheeses may be contaminated by aflatoxin-producing Aspergillus flavus during the ripening process, which has not been sufficiently taken into account. The objectives of this study were to evaluate the influence of water activity (aw), pH, and temperature on the lag phases, growth, and aflatoxin production of 3 A. flavus strains (CQ7, CQ8, and CG103) on a cheese-based medium. The results showed that the behavior of A. flavus strains was influenced by pH, aw, and temperature conditions. The CQ7 strain showed the maximum growth at pH 5.5, 0.99 aw, and 25°C, whereas for CQ8 and CQ103 strains, no differences were obtained at pH 5.5 and 6.0. In general, low pH, aw, and temperature values increased the latency times and decreased the growth rate and colony diameter, although aw and temperature were the most limiting factors. Maximum aflatoxin production on the cheese-based medium occurred at pH 5.0, 0.95 aw, and 25 or 30°C, depending on the strain. This study shows the effect of pH, aw, and temperature factors on growth and aflatoxin production of 3 aflatoxigenic A. flavus strains on a cheese-based medium. The findings may help to design control strategies during the cheesemaking process and storage, to prevent and avoid aflatoxin contamination by aflatoxigenic molds.

Impact of Simulated Human Gastrointestinal Digestion on the Functional Properties of Dietary Fibres Obtained from Broccoli Leaves, Grape Stems, Pomegranate and Tomato Peels.

This study aimed to analyse the impact of a simulated human digestion process on the composition and functional properties of dietary fibres derived from pomegranate-peel, tomato-peel, broccoli-stem and grape-stem by-products. For this purpose, a computer-controlled simulated digestion system consisting of three bioreactors (simulating the stomach, small intestine and colon) was utilised. Non-extractable phenols associated with dietary fibre and their influence on antioxidant capacity and antiproliferative activity were investigated throughout the simulated digestive phases. Additionally, the modifications in oligosaccharide composition, the microbiological population and short-chain fatty acids produced within the digestion media were examined. The type and composition of each dietary fibre significantly influenced its functional properties and behaviour during intestinal transit. Notably, the dietary fibre from the pomegranate peel retained its high phenol content throughout colon digestion, potentially enhancing intestinal health due to its strong antioxidant activity. Similarly, the dietary fibre from broccoli stems and pomegranate peel demonstrated anti-proliferative effects in both the small and the large intestines, prompting significant modifications in colonic microbiology. Moreover, these fibre types promoted the growth of bifidobacteria over lactic acid bacteria. Thus, these results suggest that the dietary fibre from pomegranate peel seems to be a promising functional food ingredient for improving human health.

Antimicrobial Properties of Essential Oils Obtained from Autochthonous Aromatic Plants.

The aim of this work was to determine the antimicrobial activity of the essential oils of six plants widely distributed in the Dehesa of Extremadura, such as Calendula officinalis, Cistus ladanifer, Cistus salviifolius, Cistus multiflorus, Lavandula stoechas, and Rosmarinus officinalis. The content of total phenolic compounds (TPC) and the antimicrobial activity of the essential oils against pathogenic and spoilage bacteria and yeasts as well as aflatoxin-producing molds were determined. A great variability was observed in the composition of the essential oils obtained from the six aromatic plants. The Cistus ladanifer essential oil had the highest content of total phenols (287.32 ppm), followed by the Cistus salviifolius essential oil; and the Rosmarinus officinalis essential oil showed the lowest amount of these compounds. The essential oils showed inhibitory effects on the tested bacteria and also yeasts, showing a maximum inhibition diameter of 11.50 mm for Salmonella choleraesuis and Kregervanrija fluxuum in the case of Cistus ladanifer and a maximum diameter of 9 mm for Bacillus cereus and 9.50 mm for Priceomyces carsonii in the case of Cistus salviifolius. The results stated that antibacterial and antiyeast activity is influenced by the concentration and the plant material used for essential oil preparation. In molds, aflatoxin production was inhibited by all the essential oils, especially the essential oils of Cistus ladanifer and Cistus salviifolius. Therefore, it can be concluded that the essential oils of native plants have significant antimicrobial properties against pathogenic and spoilage microorganisms, so they could be studied for their use in the industry as they are cheap, available, and non-toxic plants that favor the sustainability of the environment of the Dehesa of Extremeña.

Spice and Herb Frauds: Types, Incidence, and Detection: The State of the Art.

There is a necessity to protect the quality and authenticity of herbs and spices because of the increase in the fraud and adulteration incidence during the last 30 years. There are several aspects that make herbs and spices quite vulnerable to fraud and adulteration, including their positive and desirable sensorial and health-related properties, the form in which they are sold, which is mostly powdered, and their economic relevance around the world, even in developing countries. For these reasons, sensitive, rapid, and reliable techniques are needed to verify the authenticity of these agri-food products and implement effective adulteration prevention measures. This review highlights why spices and herbs are highly valued ingredients, their economic importance, and the official quality schemes to protect their quality and authenticity. In addition to this, the type of frauds that can take place with spices and herbs have been disclosed, and the fraud incidence and an overview of scientific articles related to fraud and adulteration based on the Rapid Alert System Feed and Food (RASFF) and the Web of Science databases, respectively, during the last 30 years, is carried out here. Next, the methods used to detect adulterants in spices and herbs are reviewed, with DNA-based techniques and mainly spectroscopy and image analysis methods being the most recommended. Finally, the available adulteration prevention measurements for spices and herbs are presented, and future perspectives are also discussed.

Antifungal Effect of Autochthonous Aromatic Plant Extracts on Two Mycotoxigenic Strains of Aspergillus flavus.

This study identified the compounds obtained from four native Dehesa plants, which were holm oak, elm, blackberry and white rockrose, and evaluated their ability to inhibit the growth and production of aflatoxins B1 and B2 of two strains of mycotoxigenic Aspergillus flavus. For this purpose, phenolic compounds present in the leaves and flowers of the plants were extracted and identified, and subsequently, the effect on the growth of A. flavus, aflatoxin production and the expression of a gene related to its synthesis were studied. Cistus albidus was the plant with the highest concentration of phenolic compounds, followed by Quercus ilex. Phenolic acids and flavonoids were mainly identified, and there was great variability among plant extracts in terms of the type and quantity of compounds. Concentrated and diluted extracts were used for each individual plant. The influence on mold growth was not very significant for any of the extracts. However, those obtained from plants of the genus Quercus ilex, followed by Ulmus sp., were very useful for inhibiting the production of aflatoxin B1 and B2 produced by the two strains of A. flavus. Expression studies of the gene involved in the aflatoxin synthesis pathway did not prove to be effective. The results indicated that using these new natural antifungal compounds from the Dehesa for aflatoxin production inhibition would be desirable, promoting respect for the environment by avoiding the use of chemical fungicides. However, further studies are needed to determine whether the specific phenolic compounds responsible for the antifungal activity of Quercus ilex and Ulmus sp. produce the antifungal activity in pure form, as well as to verify the action mechanism of these compounds.

An Evaluation of an Enhanced Model of Integrating Family Planning Into HIV Treatment Services in Zambia, April 2018-June 2019.

BACKGROUND: We designed and implemented an enhanced model of integrating family planning (FP) into existing HIV treatment services at 6 health facilities in Lusaka, Zambia. METHODS: The enhanced model included improving FP documentation within HIV monitoring systems, training HIV providers in FP services, offering contraceptives within the HIV clinic, and facilitated referral to community-based distributors. Independent samples of women living with HIV (WLHIV) aged ≥16 years were interviewed before and after intervention and their clinical data abstracted from medical charts. Logistic regression models were used to assess differences in key outcomes between the 2 periods. RESULTS: A total of 629 WLHIV were interviewed preintervention and 684 postintervention. Current FP use increased from 35% to 49% comparing the pre- and postintervention periods ( P = 0.0025). Increased use was seen for injectables (15% vs. 25%, P < 0.0001) and implants (5% vs. 8%, P > 0.05) but not for pills (10% vs. 8%, P < 0.05) or intrauterine devices (1% vs. 1%, P > 0.05). Dual method use (contraceptive + barrier method) increased from 8% to 18% ( P = 0.0003), whereas unmet need for FP decreased from 59% to 46% ( P = 0.0003). Receipt of safer conception counseling increased from 27% to 39% ( P < 0.0001). The estimated total intervention cost was $83,293 (2018 USD). CONCLUSIONS: Our model of FP/HIV integration significantly increased the number of WLHIV reporting current FP and dual method use, a met need for FP, and safer conception counseling. These results support continued efforts to integrate FP and HIV services to improve women's access to sexual and reproductive health services.

Application of Lactobacillus fermentum HL57 and Pediococcus acidilactici SP979 as potential probiotics in the manufacture of traditional Iberian dry-fermented sausages.

The purpose of this study was to investigate the potential of implanting the probiotics Lactobacillus fermentum HL57 and P. acidilactici SP979 during manufacture of Iberian dry-fermented sausages, and their effect on the sensory properties of these meat products. Microbial counts were studied in sausages inoculated with these strains and compared with a control batch. To detect the presence of probiotic strains at high counts (>7 log CFU/g) in the inoculated sausages, specific PCR and (RAPD)-PCR techniques were carried out. Changes due to probiotic inoculations on parameters and compounds related to fermentation, and nitrogen and lipid fractions were determined, and the impact on sensory quality evaluated by descriptive and hedonic tests. Iberian dry-fermented sausages inoculated with L. fermentum HL57 and P. acidilactici SP979 may be considered as functional products according to the counts of these strains found at the end of processing. However, inoculation with L. fermentum HL57 increased the amount of acetic acid and lipid degradation products such as malonaldehyde in Iberian dry-fermented sausages, resulting in a negative impact on relevant sensory parameters related to colour and taste. On the contrary, P. acidilactici SP979 did not notably modify the physicochemical parameters or the sensory quality of Iberian dry-fermented sausages when compared to the autochthonous microbial population present in the control batch.

Role of an autochthonous starter culture and the protease EPg222 on the sensory and safety properties of a traditional Iberian dry-fermented sausage "salchichón".

The effect of the addition of an autochthonous starter culture and the protease EPg222 on the physico-chemical and sensory characteristics of dry-fermented sausage ''salchichon" was investigated. Sausages were prepared with purified EPg222 and Pediococcus acidilactici MS200 and Staphylococcus vitulus RS34 as starter culture (P200S34), separately and together, ripened for 90 days, and compared with a control batch. Dry-fermented sausages ripened with EPg222 and starter culture showed higher amounts of AN and volatile compounds derived from amino acid catabolism than the control, especially in samples in which was added the association of enzyme and starter culture (P200S34+EPg222). There were clear differences shown by the texture analysis, with the P200S34+EPg222 batch being less hard. Especially important was the result found in biogenic amines, since the association P200S34+EPg222 reduced their accumulation compared to the EPg222 batch. The use of EPg222 may be of great interest to improve the sensory characteristics of dry-fermented sausages, but its association with the selected starter culture with low decarboxylase activity is necessary to guarantee healthiness and homogeneity.

Cyclopiazonic acid gene expression as strategy to minimizing mycotoxin contamination in cheese.

Expression of genes associated with cyclopiazonic acid (CPA) biosynthesis by Penicillium strains in a cheese-based medium has not been previously studied. To control CPA biosynthesis, it would be useful to understand the changes in gene expression during cheese production and relate them to toxin production. The objective was to evaluate the influence of pH, aw, and temperature on expression of dmaT, which encodes the enzyme dimethylallyl tryptophan synthase involved in the biosynthesis of CPA. We assayed three Penicillium strains, Penicillium commune CBS311 and CBS341 and Penicillium camemberti CBS273, using reverse transcription real-time PCR. Our results showed that the expression patterns of the gene were influenced by strain and environmental conditions. The highest expression for the P. commune strains was observed at pH 6.0, 0.95 aw, at 25 or 30 °C, depending on the strain. In contrast, P. camemberti CBS273 showed a lower dmaT expression with a maximum at 25 °C, pH 5.0 and 0.95 aw. Correlation analysis indicated that the three toxigenic strains showed a strong correlation between the relative expression of the dmaT gene and concentration of CPA under conditions simulating cheese ripening. This method could be used to control CPA production in cheese by detection of dmaT expression.

Chemical Composition and Functional Properties of Dietary Fibre Concentrates from Winemaking By-Products: Skins, Stems and Lees.

The objective of this study was to evaluate, from a technological and nutritional point of view, the chemical composition and functional properties of the industrial winemaking by-products, namely skins, stems and lees. The chemical and physical characteristics, as well as the functional properties (fat and water retention and swelling capacity, antioxidant capacity, and their prebiotic effect), of the dietary fibre of these by-products were studied. The results showed that the skins, stems, and lees are rich in fibre, with the stem fibre containing the highest amounts of non-extractable polyphenols attached to polysaccharides with high antioxidant activity and prebiotic effect. Lee fibre had the highest water retention capacity and oil retention capacity. The results reveal that winemaking by-products could be used as a source of dietary fibre with functional characteristics for food applications.

Strategies to Increase the Biological and Biotechnological Value of Polysaccharides from Agricultural Waste for Application in Healthy Nutrition.

Nowadays, there is a growing interest in the extraction and identification of new high added-value compounds from the agro-food industry that will valorize the great amount of by-products generated. Many of these bioactive compounds have shown beneficial effects for humans in terms of disease prevention, but they are also of great interest in the food industry due to their effect of extending the shelf life of foods by their well-known antioxidant and antimicrobial activity. For this reason, an additional research objective is to establish the best conditions for obtaining these compounds from complex by-product structures without altering their activity or even increasing it. This review highlights recent work on the identification and characterization of bioactive compounds from vegetable by-products, their functional activity, new methodologies for the extraction of bioactive compounds from vegetables, possibly increasing their biological activity, and the future of the global functional food and nutraceuticals market.

Improving the Viability and Metabolism of Intestinal Probiotic Bacteria Using Fibre Obtained from Vegetable By-Products.

This study evaluated the effect of dietary fibre obtained from pomegranate, tomato, grape and broccoli by-products on the gastrointestinal transit survival, growth, and metabolism of six probiotic strains. The results showed that the studied by-products contained variable amounts of polysaccharides that affected the six probiotic microorganisms in different ways. In addition, the protective effect of the fibre obtained on the probiotic strains was more effective in the case of the fibre obtained from tomato peel. In terms of growth, grape stems showed the best results, favouring the growth of lactic acid bacteria. Finally, all fibres were able to increase the content of short-chain fatty acids in the in vitro test, but broccoli stems and pomegranate peel stimulated higher production of short-chain fatty acids. The results of this study demonstrate that plant by-product fibres can improve survival, growth, and metabolism in terms of the fatty acid profiles of probiotic strains, highlighting the desirability of harnessing these by-product fibres to develop new high-value-added ingredients as probiotic carriers.

Antioxidant, Antihypertensive and Antimicrobial Properties of Phenolic Compounds Obtained from Native Plants by Different Extraction Methods.

This study aims to evaluate the efficacy of two methods (agitation and ultra-sound) for extracting phenolic compounds from 15 native plants. Plant species collected in the Dehesa of Extremadura were used. The antioxidant, antihypertensive and antimicrobial activity of the phenolic extracts was investigated. Significantly different results were obtained when comparing the two extraction methods, with the highest concentrations of phenolic compounds found for ultrasound extraction. In addition, the extracts obtained for Cistus albidus, Cistus salviifolius, Rubus ulmifolius and Quercus ilex showed the highest concentrations of phenolic compounds. The antioxidant activity was higher in the extracts of Cistus and Q. ilex obtained by ultrasound, as was the antihypertensive activity. Antimicrobial activity was also higher in the extracts obtained by ultrasound from C. salviifolius and Q. ilex plants against bacteria and from Cistus ladanifer against yeasts. Therefore, it can be concluded that, with the ultrasound extraction of phenolic compounds from C. ladanifer, C. albidus and Q. ilex plants, it is possible to obtain extracts with important functional properties, so they could be studied for their use in food with the aim of obtaining healthy and safe products, favouring the sustainability of the environment of the Dehesa Extremeña.

Addition of Grape Skin and Stems Extracts in Wines during the Storage to Reduce the Sulfur Dioxide: Impact on Red Wine Quality.

This study aimed to evaluate the usefulness of bioactive extracts obtained from red wine by-products, such as grape skins and stems, for reducing or eliminating the use of SO2 in red wine production. Special attention was focused on guaranteeing the microbiological stability of the red wines and protecting them against oxidation. Therefore, the antioxidant and antimicrobial activities of the extracts and red wines were studied. Red grape stems and skins, by-products of the wine industry, from six types of monovarietal wines, were used. Extracts obtained from stems displayed higher concentrations of total phenolic compounds and higher in vitro antioxidant activity. Both stem and skin extracts demonstrated higher antimicrobial activity against pathogenic bacteria and lower activity against yeasts. In the wines produced, higher antimicrobial and antioxidant activities were observed, mainly in the skin extract batches. This study highlights that bioactive extracts obtained from by-products of wine making could be used to reduce or eliminate the use of SO2 in wine production. In this way, healthier red wines could be obtained while guaranteeing their microbiological stability and protecting them from oxidation. Furthermore, the use of these by-products is strongly associated with the circular economy, as they could help to reduce the environmental impact of the wine industry.

Safety and functional aspects of pre-selected lactobacilli for probiotic use in Iberian dry-fermented sausages.

The purpose of this study was to investigate lactobacilli for potential probiotic use in Iberian dry-fermented sausages. A total of 18 strains, previously selected, isolated from different sources were evaluated according to safety and functional characteristics including biogenic amines and d-lactic acid production, antibiotic susceptibility, haemolysis, cell adhesion, and antimicrobial activity against food-borne pathogens. The strains Lactobacillus reuteri PL519, L. reuteri PL542, and Lactobacillus fermentum HL57 were able to establish their self on the intestinal epithelium, and an inhibition of such pathogenic bacteria as Listeria monocytogenesin vitro. These strains were also considered safe to be used with regard to their low aminogenic potential and d-lactic acid production, antibiotic resistance pattern and haemolytic activity. Thus, they were selected as a potential probiotic meat starter culture suitable for manufacture of dry-fermented Iberian sausages.

Evaluation of the microbiological safety and sensory quality of a sliced cured-smoked pork product with protective cultures addition and modified atmosphere packaging.

The aim of this study was to evaluate the effect of two protective lactic acid bacteria cultures combined with modified atmosphere packaging on the survival/growth of Listeria innocua 2030c (as a surrogate for Listeria monocytogenes) and on sensory attributes of ready-to-eat 'lombo' over storage time. Sliced 'lombo', a traditional cured-smoked pork loin, was inoculated with L. innocua 2030c, Lactobacillus sakei ST153 (isolated from 'salpicão') and BLC35 culture (with Lactobacillus curvatus, Staphylococcus xylosus and Pediococcus acidilactici; CHR Hansen) as protective cultures. Samples were packed in two modified atmosphere packaging conditions (20% CO2/80% N2 and 40% CO2/60% N2) and stored at 5 ℃ for 124 days. Both cultures led to a reduction of 1-2 log CFU/g of L. innocua 2030c after 12 h; however, at the end of storage only Lb. sakei ST153 maintained this antilisterial effect, which was more evident at 40% CO2/60% N2. The influence of cultures addition and modified atmosphere packaging conditions on the sensory characteristics of the product were not significant. Thus, Lb. sakei ST153 combined with modified atmosphere packaging is a strong candidate to be used in a biopreservation strategy maintaining the traditional sensory quality of cured-smoked pork products and increasing their safety with respect to Listeria spp.

Influence of the Use of Milk Replacers and pH on the Texture Profiles of Raw and Cooked Meat of Suckling Kids.

The aim of this work was to study the texture profile of fresh and cooked longissimus thoracis et lumborum muscle from suckling kids raised with natural milk or milk replacers. Suckling male kids from eight goat breeds (Florida, FL; Cabra del Guadarrama, GU; Majorera, MA; Palmera, PL; Payoya, PY; Retinta, RE; Tinerfeña, TI; Verata, VE), all of single parturition, were raised with milk replacers (MR) or with natural milk from the dams (NM). The meat pH, Warner-Bratzler shear force, texture profile analysis and chemical composition were determined. Kids were clustered based on their pH by k-means clustering. The effect of the rearing system on the textural profile was strongly modulated by breed. The values of Warner-Bratzler shear force and hardness found in these breeds under both rearing systems were very low. Hence, the toughness of very light suckling kids should not be a determining factor in choosing a breed or rearing system. Nevertheless, the use of milk replacers increased the presence of meat with high pH, which modified the textural parameters, decreasing the shear force but increasing cohesiveness and adhesiveness. Consequently, depending on the commercial strategy of the farm, the election of the breed and rearing system must be considered together.